1. Field
This invention is concerned with shade structures, such as umbrellas, particularly large free-standing umbrellas, which have variable geometry. In preferred embodiments, the invention provides umbrellas that comprise multiple sets of ribs supporting a canopy structure and having a mechanism associated with each set of ribs for influencing the angle or elevation of the rib sets.
2. Description of the Related Art
Shade structures, and in particular umbrellas, have long been known that comprise a pole supporting a set of ribs to which is attached a fabric canopy and having a mechanism mounted to the pole that operates to extend or retract the ribs and thereby raise or lower the canopy.
As use of outdoor restaurants, patios and gardens and the like becomes more popular, so there is an increasing demand for shade structures that are more flexible, visually appealing or offer enhanced features or ease of operation.